[PATCH 4.19 22/66] ASoC: dapm: Fix NULL pointer dereference in snd_soc_dapm_free_kcontrol

[Greg Kroah-Hartman]

[ Upstream commit cacea3a90e211f0c111975535508d446a4a928d2 ]

w_text_param can be NULL and it is being dereferenced without checking.
Add the missing sanity check to prevent  NULL pointer dereference.

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@xxxxxxxxx>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 sound/soc/soc-dapm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 9b78fb3daa7bb..2257b1b0151c4 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -3847,6 +3847,10 @@ snd_soc_dapm_free_kcontrol(struct snd_soc_card *card,
 	int count;
 
 	devm_kfree(card->dev, (void *)*private_value);
+
+	if (!w_param_text)
+		return;
+
 	for (count = 0 ; count < num_params; count++)
 		devm_kfree(card->dev, (void *)w_param_text[count]);
 	devm_kfree(card->dev, w_param_text);
-- 
2.20.1